Web Content Filtering
The Internet is growing at such a rate that many of the large search engines such as Google and Yahoo are unable to keep track of all the sites that they currently index. This rapid growth has meant that is it now impossible to implement comprehensive filtering using website addresses (URLs) alone.
Filtering content from websites is now a major concern, especially when there are children involved. Web content filtering involves the identification of subject terms such as drugs, pornography, profanities, racism or hate etc and disallowing access to them if unsuitable.
The problem with most commercial web content filtering packages and software based firewalls is the expensive licensing fees that are invariably associated with them.
Open Source Web Filtering Solutions
There currently exist a number of open source solutions for web content filtering, one of them being Dan's Guardian. This can be used to prevent online access to objectionable material such as malware or spyware, thus protecting your network.
Access is controlled via criteria that you can specify. Using this criteria, the software is able to analyse a website to determine whether or not it violates your filtering rules. If it does then an access denied page is displayed.
It is also possible to exclude certain users from filtering rules, such as administrators. In addition to this, special permissions can be put into place that will allow a user / users access to a previously blacklisted website.
When used on conjunction with other open source solutions, a network can be protected against spyware, adware and virues. By preventing the installation of these onto a network, the hassle of having to continually scan and remove spyware is eliminted. This will in turn save administrators time and frustration.
